Field of the Invention
The present invention relates to vehicles, and particularly, air conditioning of vehicles.
Description of the Background Art
Pre-air conditioning to perform air conditioning of a vehicle before a user rides in the vehicle has previously been known. Pre-air conditioning is performed to reduce a thermal discomfort when the user rides in the vehicle. In an electric vehicle or a hybrid vehicle (which may also be simply referred to as a “vehicle” hereinafter) that uses the electric power of a battery as a running source, electric power consumed by an air conditioning apparatus used for the pre-air conditioning is supplied from, for example, the battery and a power supply outside the vehicle (external power supply) connected to the vehicle to charge the battery (see Japanese Patent Laying-Open No. 2012-076517, for example). Pre-air conditioning may be performed while the user is not in the vehicle, by setting a timer or by remote operation (remote air conditioning).
The user may often cause the vehicle to run immediately after the completion of charging the battery. In that case, the pre-air conditioning is performed during charging of the battery. That is, electric power from the external power supply is used for both charging of the battery and the pre-air conditioning. Consequently, electric power for charging the battery decreases by the amount of power consumption by the pre-air conditioning, and thus, it takes time to charge the battery.
Moreover, the user may sometimes cause the vehicle to run after a short time from the completion of charging the battery. In that case, the pre-air conditioning is performed after the completion of charging the battery. When charging of the battery has been completed, a charging cable for connecting the external power supply to the vehicle may have been removed from the vehicle. At this time, since the vehicle cannot utilize electric power from the external power supply, the pre-air conditioning is performed with the electric power of the battery. Consequently, the state of charge (SOC) of the battery will decrease.
Japanese Patent Laying-Open No. 2012-076517 suggests control to gradually reduce an upper limit value of power consumption by the pre-air conditioning, as time passes. In this way, the SOC of the battery is prevented from decreasing in the pre-air conditioning. Such control involves consumption of a large amount of electric power at the beginning of the pre-air conditioning, resulting in large power consumption (amount of electric power consumed) by the pre-air conditioning.